EV calculator finds cheapest car for your commute

Electric-car aficionados love to brag about the low cost of filling up with a power plug, especially when gasoline prices rise.

But which EV has the lowest cost for your own daily commute? A new online calculator can show you, in exacting detail.

Image courtesy UC Davis Institute of Transportation Studies

Crafted by the UC Davis Institute of Transportation Studies, the EV Explorer allows you to enter specifics of your commute and then see which cars would give you the lowest annual energy cost, whether the money is spent on electricity, gasoline, or in the case of plug-in hybrids, both.

The results aren’t always obvious.

For example, the cheapest car for my 6-mile round-trip commute from the Haight to downtown San Francisco would not be an all-electric car, according to EV Explorer. Instead, it would be a new Toyota Prius plug-in hybrid, with an annual energy cost of $64.

Next up would be the electric Nissan Leaf, at $66, then the Chevy Volt advanced hybrid at $77. For comparison, the all-gas 2014 Honda Civic would cost $180 in annual energy costs.

My wife’s commute to downtown Berkeley is a different story. For her, the Leaf is the best bet, with $339 in annual energy costs. The plug-in Prius would consume $513 in gasoline and electricity per year, while the Civic would cost $929.

(And before anyone asks, no, neither of us drives to work on a regular basis. We remain BART and Muni commuters. In spite of everything.)

The EV Explorer has one big drawback. It does not yet include a way to factor in the initial price of buying the car in the first place — a big issue, since plug-in cars still cost more than their gas-burning competitors. The researchers who created the online calculator want to add that later, along with the cost of insurance.

But the EV Explorer does allow users to customize the data in many ways. You can enter the specific prices you pay for electricity and gasoline, rather than relying on the default values of 14 cents per kilowatt-hour and $3.70 per gallon. If your company offers free EV charging at work, you can specify that, too.

You can also compare specific cars. Want to see how much commuting with a Tesla Model S would cost each year? No problem.

“We want to let people play around with it,” said lead researcher Michael Nicholas, with UC Davis’ Plug-in Hybrid and Electric Vehicle Research Center. “Or they can get in and out pretty quickly, if they want to.”